Unit for feeding filters to a filter tip attachment machine

ABSTRACT

Filter plugs for cigarettes are supplied to a filter tip attachment machine by a feed unit comprising a hopper into which filter plugs of at least one type are directed in succession from a filter maker. The hopper is positioned above a row of rotating drums, each furnished peripherally with a plurality of aspirating axial flutes by which the filters are taken up singly from the hopper and directed to a transfer station; here, the flutes are aligned axially one by one with the inlet of a pneumatic feed duct connecting with the filter tip attachment machine. The hopper is equipped with sliding baffles by which it can be partitioned to create at least two sectors, each serving at least one drum, so that filters of different length can be handled simultaneously, and the unit is able to operate in conjunction with filter makers and filter tip attachment machines of more than one type upstream and downstream.

BACKGROUND OF THE INVENTION

The present invention relates to a unit for feeding filters to a filter tip attachment machine.

In particular, the invention relates to a filter feed unit equipped with a holding hopper, located between the outfeed of a filter maker and the inlet of a pneumatic feed duct connected in turn to a filter tip attachment machine.

Conventionally, filters turned out by the maker are directed into the hopper, which functions as a reservoir, by way of a single infeed point in the top part of the selfsame hopper. The filters are collected en masse internally of the hopper, ordered horizontally and side by side, ready to be transferred to the pneumatic feed duct.

The hopper presents a single internal compartment accommodating filters of one type, hence all of the same diameter and the same length.

The transfer of the filters from the outlet of the hopper to the inlet of the feed duct is brought about, again conventionally, through the agency of transfer means comprising a plurality of drums rotating about respective horizontal axes parallel to the axes of the filters and located in the lower part of the hopper.

The drums are furnished around the periphery with aspirating flutes, disposed parallel to the axis of the drum, each one of which is able to accommodate a single filter.

Gravitating from the reservoir, the filters are taken up by the aforementioned flutes and rotated through 180° on the drums, passing singly and in succession into a transfer station where they are drawn into a flow of compressed air and conveyed along the pneumatic feed duct to the filter tip attachment machine.

A conventional filter feed unit is fed generally, during operation, with filters of one length and one diameter. The space enclosed by the hopper can be varied, when not in operation, by displacing the back wall to adapt the depth of the selfsame hopper to the length of the incoming filters.

Thus, as already intimated, each unit handles filters of just one type and is dedicated to a sole filter maker on the infeed side, and a sole filter tip attachment machine on the outfeed side.

Alternatively, the filter feed unit can be used in conjunction with multiple filter tip attachment machines processing the same type of filter but operating at dissimilar speeds one from another. In this instance, different numbers of drums will be dedicated to the various downstream machines, according to their operating speed.

It will be seen from the foregoing outline that the filter feed unit lacks versatility, since only one brand of filter can be handled, and a single unit can be used only with certain filter makers and filter tip attachment machines.

Moreover, it is not always possible to exploit all of the sets of drums by reason of the possible variations in operating speed of the downstream attachment machine, so that the output capacity of the machinery overall is limited.

The object of the present invention is to improve the versatility of a unit for feeding filters, by enabling it to handle filters of different lengths simultaneously.

A further object of the invention is to render the filter feed unit suitable for use with multiple filter makers or filter tip attachment machines utilizing different sizes of filters or operating at dissimilar speeds.

SUMMARY OF THE INVENTION

The stated object is realized according to the present invention in unit for feeding filters to a filter tip attachment machine, comprising a hopper in receipt of at least one succession of cigarette filter plugs, from which the selfsame filters are subsequently dispensed, and a plurality of drums positioned at the bottom of the hopper, each rotatable about a substantially horizontal axis and furnished peripherally with a plurality of aspirating axial flutes by which the filters are taken up singly from the hopper and passed on to a transfer station where the flutes assume a position of axial alignment with the inlet of a pneumatic feed duct along which the filters are directed toward the filter tip attachment machine.

The feed unit further comprises means by which the hopper can be partitioned into at least two sectors, each serving at least one drum.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which:

FIG. 1 is a front perspective view of a unit for feeding filters according to the present invention, illustrated in a preferred embodiment;

FIG. 2 is a schematic front elevation view of the preferred embodiment as in FIG. 1;

FIG. 3 is a rear perspective view of the preferred embodiment as in FIG. 1;

FIG. 4 is a schematic rear elevation view of the preferred embodiment as in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIG. 1, numeral 1 denotes a feed unit, in its entirety, by which filter plugs 2 are supplied to a filter tip attachment machine of conventional type, not illustrated.

The unit 1 comprises a frame-like structure 3 with a lower base portion 4 incorporating bearers, ducts and control systems of familiar type not described further, and an upper portion carrying a hopper 5 delimited by a front wall 6 and a back wall 7, interconnected by two side walls 8 and 9.

The side walls 8 and 9 include first segments rising vertically from the base portion, and second segments converging toward the top, so that when seen in longitudinal section, the hopper 5 presents the shape substantially of an upturned funnel.

The front wall 6, made preferably of transparent material and appearing substantially rectangular in outline, is composed of two doors 6 a and 6 b that can be opened to allow inspection and servicing of the hopper 5 on the inside.

The back wall 7, on the other hand, is delimited by the side walls 8 and 9 and therefore assumes the same upturned funnel shape as that of the hopper 5.

The frame-like structure 3 further comprises a vertical bulkhead 10 carrying the hopper 5, facing the back wall 7 and connected to the side walls 8 and 9.

Filter plugs 2 turned out by a filter maker (not illustrated), located upstream of the unit 1, are directed into the hopper 5 and allowed to collect one alongside another, disposed perpendicular to the front and back walls 6 and 7.

The hopper 5 is delimited at the bottom by a plurality of drums 11, each set in rotation about a respective longitudinal axis 12 perpendicular to the front and back walls 6 and 7.

Each drum 11 presents a plurality of aspirating axial flutes 13 arranged around the periphery in conventional manner and serving each to accommodate a single filter 2.

The bottom part of the hopper 5 is enclosed by a plurality of transparent flaps (not illustrated) arranged one beside another. The flaps are located one directly in front of each drum 11, so that the drums 11 can be exposed and inspected singly in the event of a jam or malfunction occurring.

As indicated in FIG. 1, each drum 11 presents a loading station 14 above, where the filters 2 are taken up singly and in succession by the peripheral axial flutes 13, and an unloading and transfer station 15 below, coinciding with the inlet of the pneumatic feed duct that links the unit 1 to the filter tip attachment machine (not illustrated).

The hopper 5 further comprises means 16 by which to partition the storage space into at least two sectors 17, each serving at least one drum 11. Such means 16 are illustrated as at least one movable baffle 18 disposed vertically and parallel to the side walls 8 and 9.

The baffle 18 is translatable along a direction parallel with the axes 12 of the drums 11 between a fully retracted position, outside of the hopper 5 and to the rear of the bulkhead 10, and a fully extended position inside the hopper 5, bridging the gap between the front wall 6 and the back wall 7.

Accordingly, the bulkhead 10 is furnished with vertical slots 19 through which the baffles 18 are able to pass.

In the preferred embodiment of FIG. 1, shown purely by way of example, the unit 1 is equipped with three baffles 18 by which the space internally of the hopper 5 can be divided into four sectors 17 appearing as two distinct identical pairs. The hopper 5 is symmetrical relative to a vertical axis coinciding with the central baffle 18, so that the two sectors 17 a and 17 b outermost are mutually identical and the two sectors 17 c and 17 d innermost are mutually identical. Each outer sector 17 a and 17 b serves two drums 11; each inner sector 17 c and 17 d serves a single drum 11.

Each baffle 18 can be operated individually and independently of the others, allowing the hopper 5 to be partitioned as preferred and as may be most appropriate.

In the preferred solution of FIG. 1, different configurations can be created, depending on which and how many of the baffles 18 are brought into operation and advanced toward the front wall 6.

The single sectors 17 operate independently of one another, and their allocation to the drums 11 can be selectively predetermined.

In the example of FIG. 1, where the unit 1 is shown with six drums 11 and three baffles 18, the baffles can be retracted or extended to produce the following configurations:

three sectors 17, with each sector 17 serving two drums 11,

two sectors 17, with each sector 17 serving three drums 11,

two sectors 17, with one sector 17 serving two drums 11 and the other serving four drums.

Accordingly, the hopper is able to handle filters of different types simultaneously.

The filter feed unit 1 is equipped further with means 20 by which to vary the size of at least one sector 17 in the partitioned hopper 5. The means 20 in question comprise at least one movable panel 21 associated with the back wall 7. In a preferred solution, each sector 17 presents one such movable panel 21 delimiting the rear of the sector 17 and coinciding with the back wall 7.

Each panel 21 is translatable, remaining parallel to the front wall 6, in such a way as to vary the depth of the relative sector 17.

In the preferred solution of FIG. 1, the hopper is furnished with four panels 21 which, like the sectors 17, are arranged in two distinct identical pairs arranged symmetrically on either side of the vertical axis aforementioned.

The movement of each single panel 21 is brought about independently relative to the movement of the others so that individual sectors 17 can be adapted to accommodate filters 2 of different length.

A top part of the hopper 5 affords openings 22 to admit the filters 2. With reference in particular to the example of FIG. 1, the hopper 5 presents three openings 22, namely a central opening 22 a by way of which the two inner sectors 17 c and 17 d are filled, and two side openings 22 b by way of which the two outer sectors 17 a and 17 b are filled.

More exactly, when the hopper 5 is partitioned only by the central baffle 18 into two sectors 17, each serving three drums 11, filters 2 are admitted solely through the side openings 22 b. In the other two possible configurations, with three sectors 17 each serving two drums 11, and with two sectors 17 serving two and four drums 11, filters will enter both through the side openings 22 b and through the central opening 22 a.

The top part of the hopper 5 is equipped further with a plurality of photocells 23, at least one to each sector 17, serving to monitor the level of the filters 2 amassed within the enclosure.

The photocells 23 are wired to a control unit (not illustrated) operating in conjunction with the filter maker upstream of the feed unit 1, in such a way that when the sectors 17 fill up to a certain level, the flow of filters 2 from the maker to the hopper 5 will be suspended temporarily.

Equipped with the baffles 17 and the panels 21, accordingly, the feed unit 1 is able to operate in a system incorporating multiple machines handling filters 2 of different sizes, given that the space encompassed by the hopper 5 is partitioned in such a way so as to create a plurality of sectors 17 operating independently of one another and in conjunction with respective drums 11.

Located above each drum 11 and to one side of the loading station 14 is an element 24 presenting a surface 24 a angled downward toward the drum 11 and serving to restrict the cross sectional area of the passage afforded to the filters 2 at the selfsame station 14. This arrangement is designed to reduce the weight of the column of filters 2 bearing down on the loading station 14.

The means 16 for partitioning the inside of the hopper 5 further comprise an actuator 25, as shown in FIGS. 3 and 4, associated with the relative baffle 18 and connected rigidly to the vertical bulkhead 10 of the feed unit 1.

The actuator 25 in question serves to bring about the sliding movement of the baffle 18, and consists in a pneumatic cylinder 26.

Each baffle 18 presents a projection 18 a that stays permanently outside the hopper 5 and carries a rectilinear hanger 27 engaging slidably with a linear track 28 of “C” profile connected to the bulkhead 10, externally of the hopper 5.

The action of the cylinder 26 is transmitted to the projection 18 a, likewise of “C” profile, by way of a bracket 29 anchored to the underside of the projection 18 a.

The projection 18 a, the rectilinear carriage 27, the linear track 28 and the pneumatic piston 26 are positioned at the top end 19 a of the slot 19.

The projection 18 a also limits the travel of the baffle 18 inasmuch as the underside, to which the bracket 29 is attached, is disposed transversely to the slot 19 and thus prevented by the bulkhead 10 from advancing further once the baffle 18 is fully inside the hopper 5.

Each of the vertical slots 19 in which the baffles 18 slide back and forth is flanged by two matched guide plates 30 serving to ensure that the baffle 18 will not slip out of its correct position when fully retracted.

In a preferred embodiment, means 20 for varying the size of at least one sector 17 of the hopper 5 will further comprise at least one drive unit 31 mounted to the vertical bulkhead 10 and associated with a respective movable panel 21, as illustrated in FIG. 3 and described hereinafter.

Each such drive unit 31 is carried by a mounting plate 32 attached to the bulkhead 10 externally of the hopper 5 by way of a first stud 33 a and a second stud 33 b, both of which occupying a fixed position.

The drive unit 31 comprises an electric motor 34 coupled to a speed reducer 35 driving a gear 36. The gear 36 is coupled in turn by way of a chain 37 or a belt with two further gears 38, also mounted to the bulkhead 10 on the outside of the hopper.

Each mounting plate 32 is pivotable about the first stud 33 a and affords a slot 39, engaged by the second stud 33 b, which is lockable so as to secure the plate in the most advantageous position. The resulting mechanism allows a degree of movement to the drive unit 31, which is used to adjust the tension of the chain 37.

Each of the two driven gears 38 presents a center hole 40 coinciding with a respective hole in the bulkhead 10. Each hole 40, in turn, is engaged by an externally threaded rod 41 fastened rigidly to the surface of the panel 21 facing the bulkhead 10.

Located between the rod 41 and the center hole 40 of each driven gear 38 is a mechanism, such as a ballscrew, allowing the rod 41 to stroke back and forth through the hole 40 and displace the relative panel 21.

The first gear 36 is set in rotation by the electric motor 34 and transmits motion by way of the chain 37 to the other two gears 38. The angular motion of the two driven gears 38 is transmitted through the ballscrew mechanisms to the rods 41 and converted into linear motion, with the result that the panel 21 to which the rods are anchored will be pushed forward or drawn back.

Each electric motor 34 is fitted with an encoder, not illustrated, that will determine the distance of the associated panel 21 from the front wall 6 of the hopper 5. Thus, it becomes possible to assign each sector 17 to a different type of filter 2 on the basis of length.

The operation of the actuator 25 and the electric motor 34 is piloted by a control unit 42 such as will allow the position of the baffle 18 and of the panel 18 to be altered either automatically or in manual mode, by an operator, so as to adapt each sector 17 to the type of filter 2 accommodated.

In the example of FIG. 1, preferably, up to three different types of filter can be handled, in terms of length and diameter, and accordingly, the single feed unit 1 can be linked both on the infeed and on the outfeed side to three different types of filter maker and filter tip attachment machine.

Alternatively, the feed unit 1 can be linked to similar machines operating at different speeds. 

1. A unit for feeding filters to a filter tip attachment machine, comprising: a hopper in receipt of at least one succession of cigarette filter plugs, from which the selfsame filters are subsequently dispensed; a plurality of drums positioned at the bottom of the hopper, each rotatable about a substantially horizontal axis and furnished peripherally with a plurality of aspirating axial flutes by which the filters are taken up singly from the hopper and passed on to a transfer station where the flutes assume a position of axial alignment with the inlet of a pneumatic feed duct along which the filters are directed toward the filter tip attachment machine; means by which the hopper is partitionable into at least two sectors, each serving at least one drum.
 2. A unit as in claim 1, wherein the means by which the hopper is partitionable into at least two sectors comprise at least one translatable baffle.
 3. A unit as in claim 2, wherein the means by which to partition the hopper comprise three baffles creating four sectors.
 4. A unit as in claim 1, further comprising means by which to vary the size of at least one of the partitioned sectors created in the hopper, so as to accommodate filters of different length.
 5. A unit as in claim 4, of which the hopper comprises a front wall and a back wall, interconnected by two side walls and set apart at a prescribed distance, wherein means by which to vary the size of a partitioned sector operate by varying the prescribed distance between the front and back walls.
 6. A unit as in claim 5, wherein the means by which to vary the prescribed distance comprise at least one movable panel associated with the back wall.
 7. A unit as in claim 6, wherein the means by which to vary the prescribed distance comprise four movable panels.
 8. A unit as in claim 1, wherein the hopper presents at least two openings through which filter plugs are admitted to at least two partitioned sectors created in the hopper.
 9. A unit as in claim 2, wherein the means by which the hopper is partitionable into at least two sectors comprise at least one actuator associated with the at least one translatable baffle.
 10. A unit as in claim 9, wherein the at least one actuator comprises at least one pneumatic cylinder by which motion is induced in the associated translatable baffle.
 11. A unit as in claim 6, wherein the means by which to vary the size of at least one of the at least two partitioned sectors created in the hopper further comprise a drive unit associated with the at least one movable panel.
 12. A unit as in claim 11, wherein the drive unit comprises an electric motor by which the at least one movable panel is operated.
 13. A unit as in claim 1, further comprising photocells serving to monitor the level of the massed filters occupying each of the at least two partitioned sectors created in the hopper.
 14. A unit as in claim 9, comprising a control unit connected to the at least one actuator and to the at least one drive unit, by which the position of the at least one baffle and the at least one panel can be varied automatically in order to adapt the feed unit to a given type of filter.
 15. A unit as in claim 11, comprising a control unit connected to the at least one actuator and to the at least one drive unit, by which the position of the at least one baffle and the at least one panel can be varied automatically in order to adapt the feed unit to a given type of filter.
 16. A unit as in claim 2, further comprising means by which to vary the size of at least one of the partitioned sectors created in the hopper, so as to accommodate filters of different length.
 17. A unit as in claim 3, further comprising means by which to vary the size of at least one of the partitioned sectors created in the hopper, so as to accommodate filters of different length. 